AirVeraCity Nodes

JSON data format

The JSON files contain a JSON document with the following structure:

    columns: ["timestamp", "substance 1", "substance 2", ...],
    rows: [
        [timestamp 1, value 11, value 12, ...],
        [timestamp 2, value 21, value 22, ...],

Timestamps and values are numbers. Missing values are null.

TSV data format

The TSV files contain tab-separated values:

timestamp      substance 1    substance 2    ...
timestamp 1    value 11       value 12       ...
timestamp 2    value 21       value 22       ...

The first line contains the columns headers. Missing values are denoted by a single dash (-).


The timestamp values denote milliseconds since epoch. Virtually all environments provide functions to convert such values to their internal date representation:

Python datetime.fromtimestamp(timestamp / 1000, timezone.utc)
Perl gmtime($timestamp / 1000)
JavaScript new Date(timestamp)
Java new Date(timestamp)
Shell date -d @timestamp
Excel = (A2 / 86400000) + DATE(1970, 1, 1)


The following substances are reported:

Column Substance Unit

HTTP/REST interface

The data can be retrieved through HTTPS. The following request retrieves the last 7 days of sensor 23009 as JSON document:

Accepted parameters are:

sensor the sensor ID
timestamps indicating the desired range, defaults to the last 7 days
format json (default) or tsv

The following request retrieves the measurements of sensor 23009 that lie in the indicated time range as TSV document: